Coilover Dampers for a LeGrand MK 18

[APBos]

Could someone guide me to sizing coilovers to a chassis? Since the body of my car is a LeGrand, but the chassis is at a minimum a modified LeGrand MK18/25 chassis I would like to learn how to calculate the size of the dampers/shocks. A starting point might be the recommended Koni adjustable shock, but I have found no reference to what size they are.

Regards
Paul

[Hawke]

Put the car at the correct ride height. Measure the lengths. Call it B. Raise the chassis 2”. Measure again. Call it A. Put chassis on ground. Call it C.

A-C = stroke. C to B should be 2/3 of A to C. Bump should be 2/3 of stroke, rebound 1/3.

I sell a lot of shocks for old race cars. This method works pretty well. Never use the length of the existing shock as being correct, even if it is the original. Most shocks are made in 1” increments. If you have to compromise, make rear longer, front shorter. Some manufacturers will have longer top eyes in 1/4” increments.

You must have adequate rebound on the rear. At ride height, tilt the chassis 3 degrees. If you haven’t overextended the shock, it’s a good start.

[APBos]

Excellent. Thank you!